Chest movement during breathing is controlled by the inspiratory and expiratory muscles, including the diaphragm and rib cage muscles. Respiratory muscle function is described in terms of muscle strength and muscle endurance. A number of diseases result in respiratory muscle dysfunction, including stroke, congestive heart failure, emphysema, chronic bronchitis, neuromuscular diseases and the like, reducing respiratory muscle strength and/or endurance. Advanced age can also lead to decreased function of the respiratory muscles. Like other muscles in the body, the inspiratory muscles can be trained for strength and endurance. For the purposes of this invention, strength exercises are those designed to have a large load for a short duration, while endurance exercises have a lighter load for a longer period of time.
Research has been devoted to measuring muscle strength and muscle endurance, as well as establishing normative values. Respiratory therapists are trained to test respiratory muscles. A number of hand-held spirometers are available to measure muscle strength. However, little has been done to rehabilitate muscles rendered dysfunctional as a result of disease. The health care industry does not seem to have realized the value of training these muscles in a manner similar to training of other muscles in the body.
In “Evaluation . . . ”, herein incorporated by reference, values of inspiratory muscle strength and inspiratory muscle endurance were measured by flow-resistive loads for a group of 68 people for the purpose of establishing normative values. After the single test value was obtained, the researchers failed to take the steps necessary to try to improve the muscle function.
There are some devices on the market that can be used to exercise the inspiratory muscles. Many of these devices merely have the patient breathe against an inspirational load. No feedback is provided to the patient as to whether the exercise is being done correctly, or of there is improvement in the inspiratory muscle function. Few of these devices address endurance training at all.
There is, therefore, a need in the art for a system and method of testing and exercising the endurance of the inspiratory muscles. Data from the tests and exercises are used to set parameters for subsequent exercise sessions so that muscle endurance continues to develop.